Record transcriber adaptively responsive to typing activity

ABSTRACT

A RECORD TRANSCRIBER WHICH RELIEVES A TYPIST OF THE NEED TO STOP AND RESTART RECORD TRANSPORTER INCLUDES A CONTROL SYSTEM FOR MODIFYING RECORD DRIVE SPEED IN RESPONSE TO TYPING RATE.   D R A W I N G

United States Patent 1 Goldman 111 3,829,621 Aug. 13, 1974 RECORD TRANSCRIBER ADAPTIVELY RESPONSIVE TO TYPING ACTIVITY [21] App]. N0.: 249,902

[52] US. Cl 179/100.l R, 179/100.1 VC [51] Int. Cl. Gllb 15/18 [58] Field of Search 1'79/100.1 R, 100.1 VC,

SIGNAL [56] References Cited UNITED STATES PATENTS 3,614,336 10/1971 Patey 179/100.1 VC

Primary Examiner-Rhymond F. Cardillo, Jr. Attorney, Agent, or FirmElmer R. Helferich et al.

[57] ABSTRACT A record transcriber which relieves a typist of the need to stop and restart record transport includes a control system for modifying record drive speed in response to typing rate.

18 Claims, 4 Drawing Figures RESPONSIVEI I 7 RATE S'GNAL DETECTOR GENERATOR 26 TRANSPORT I MOTOR ENERGIZER 24 I l TRANSPORT MOTOR SPEED I MODIFIER I 28 I TRANSCRIBER RECORD TRANSPORT MOTOR PATENTEU 3.829.621

Q Z6 TRANSPORT F 6 MOTOR I ENERGIZER I6 20 24 i I KEYSTROKE TRANSPORT RESPONSIVE :22- 3 MOTOR l5 S'GNAL oETEcToR SPEED GENERATOR MODIFIER I /Z TRANSCRIBER I RECORD TRANSPORT.

MOTOR 54 7 m3 52 R27 J F/ 1 R28 RECORD TRANSCRIBER ADAPTIVELY RESPONSIVE TO TYPING ACTIVITY FIELD OF THE INVENTION This invention relates to record playback machines, such as magnetic record transcribers, used in reproducing pre-recorded speech for the typing of the information content thereof. The invention pertains more particularly to automated transcribers of the type which relieve typists of the need to control the stopping and restarting of the transcriber record transport after initial starting.

BACKGROUND OF THE INVENTION Conventional record transcribers in widespread current use in secretarial typing pools and the like are generally equipped with a foot-operated switch assembly by which the typist controls the stopping and restarting of the transcriber record transport to correlate her typing activities with the audible signals generated by the transcriber. In the interests of reducing typist fatigue and in rendering typing activity itself more efficient, various efforts have been undertaken to automate such transport stopping and restarting function.

Presently known automated transcribers apparently resulting from such efforts reflect a common approach which renders them less efficient than is desired. Thus, in US. Pat. No. 3,614,336, No. 3,532,835 and No. 2,410,835 and in British Pat. No. 776,656, the record being transcribed is regarded as the optimum source of automating control information and the transcribers of these patents accordingly incorporate circuit means operative either to detect actual speech pauses in the record being transcribed or to determine, e.g., by detecting syllables, an appropriate point at which a pause should be created. Record transport is discontinued based on such pause detection or pause creation. Less than desired efficiency is inherent in such known transcribers since, in the first instance, such circuit means cannot distinguish between recorded information comprising mere instructions to the typist and recorded information comprising matter to be typed. These transcribers thus discontinue record transport on actual and created pauses and hence at times unnecessarily discontinue transcriber operation. As in US. Pat. No. 3,614,336, switches need be provided such that the typist can discontinue operation of the automating control system of the transcriber when she confronts recorded instructions. Secondly, while actual pauses may be readily detected, the alternative and perhaps essential function of creating pauses for typist convenience requires complex detection fraught with error possibilities, namely, syllable counting. The less than desired efficiency in known automated transcribers is also attributable to their lack of concern for the actual typing activities of the typist. Thus, the transcribers disclosed in all of the above-referenced patents, except for US. Pat. No. 3,614,336, do not include in their automating control systems means for monitoring typing activities and hence are clearly not typist-adaptive.

In operation of the transcriber of US. Pat. No. 3,614,336, primary automating control information is derived by continually detecting and counting the syllable content of recorded information. Record transport is discontinued where a syllable count in excess of a preselected count is attained and is restored after typing activity, as detected by a transducer, ceases. The typing activity transducer output is also examined, for secondary automating control, to determine the rate of typing activity. Such rate information is combined subtractively with syllable count such that, as typing speed increases, the syllable count required for record transport discontinuance is not attained as readily as primary automating control information would direct. While such transcriber appears at first glance to be adaptive to typist activity, it invites a runaway situation and is evidently non-adaptive and clearly inefficient in the common instance where a typist is endeavoring to increase her speed to catch up" with the record. As her speed increases, the transcriber of this patent directs that the effectiveness of primary control be diminshed by secondary control and that the record transport continue.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved transcriber effectively eliminating the need for typist control of stopping and restarting of the transcriber record transport.

In the efficient attainment of the foregoing and other objects, the invention provides a transcriber which, in the first instance, derives control information for both stopping and restarting its record transport from typing activity. As such, the transcriber of the invention implements a control loop which is at all times inclusive of the typist as a control therefor. Accordingly, the transcriber is completely adaptive to the needs of the typist in controlling its record transport.

In its preferred form, the transcriber of the invention includes first means generating an electrical output signal on the occurrence of each operation of a typing key, second means generating output signals indicative of the rate of occurrence of signals generated by the first means and third means operative to decrease record transport where such occurrence rate indication exceeds a first preselected rate and thereafter operative to increase record transport where such occurrence rate indication is less than a second preselected rate. The invention contemplates both a complete stopping and restarting of the transcriber record transport and- /or simple variation in record transport between such extremes.

The foregoing and other objects and features of the invention will be evident from the followingdetailed description of the invention and from the drawings in which like numerals are used to identify like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagrammatic showing of the transcriber of the invention.

FIG. 2 is a detailed schematic drawing of a preferred embodiment of the automating control system of the invention.

FIGS. 3 and 4 are detailed schematic drawings of optional circuit means employable in conjunction with the FIG. 2 system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, transcriber 10 includes customary reproducing means (not shown) for converting magnetic or like pre-recorded signals into audible signals for use by a typist in typing the information therein. Typically, such transcriber further includes a record transport motor 12 which is energized at first levels for operation at preset speed by an energizer 14 which is responsive to typist manipulative input, e.g., operation of the transcriber PLAY push-button, to 'provide first level excitation to the motor over connection 15. For typist convenience in starting and stopping motor 12, connection 15 generally includes a footoperated switch. As indicated by the broken line showing thereof in FIG. 1, connection 15 is not required in transcribers of the invention. In place thereof, the invention contemplates the use of an automating control system adaptively responsive to actual typing activity to provide direct and/or variable interconnection of motor 12 and energizer 14 or disconnection of these units.

As illustrated in functional block diagrammatic form in FIG. 1, such system includes a keystroke-responsive signal generator 16 which provides an output signal on line 18 upon each operation of a key by a typist. As discussed below, this generator is preferably a microphone providing an output signal on the impact of each operated key and a typewritter platen. The generator may readily comprise other means so operating, e.g., as in certain electric typewriters which generate a pulse for each key operation. A signal rate detector 20 provides a signal on line 22 indicative of the rate of occurrence of signals applied thereto by generator 16. Circuit means 24 provides connection between line 26 connected to energizer 14 and line 28 connected to motor 12 and is effective to modify motor speed in accordance with the signals on line 22. By way of further general description of the FIG. 1 system, the line 22 sig nal preferably comprises a direct current signal and modifier 24 is operatively responsive to line 22 signals of greater than a predetermined amplitude, i.e., indicative of line 18 signal occurrence rate in excess of a first preselected rate, to disconnect units 12 and 14 and thereafter, on the receding of the line 22 signal amplitude to an amplitude less than another predetermined amplitude, i.e., indicative of line 18 signal occurrence rate less than a second preselected rate, to resume interconnection between the units. Between such extreme activities, modifier 24 is effective to provide variable interconnection of units 12 and 14 on the occurrence of line 22 signals of amplitude intervening such predetermined amplitudes. The system and its operational facets will be further understood from a consideration of the preferred embodiment thereof illustrated in the detailed schematic diagram of FIG. 2. The system circuit components are identified below in Table I with typical component values.

In FIG. 2, signal generator 16 is comprised of microphone 30 having sensitivity sufficient to provide an output signal on line '18 on each impact of a typing key on the typewriter platen. Signal rate detector 20 of FIG. 2 is comprised of five stages. The line 18 signals are amplified in stage 32 incorporating transistor 01. Second stage 34 includes 02, effective to invert, rectify and clip the output signals of Q1, and a selective charge storing circuit comprised of diode D1 and capacitor C4. Stage 36 comprises a monostable multivibrator including Q3 and Q4, operative to generate output pulses of like character despite variation in the character of input signals thereto attributable to distance variations between signal generator 16 and the operated key, and

like factors. Stage 38 comprises a dynamic averaging circuit including capacitor C6 which, while being selectively charged by stage 36 through D3 and R12, can discharge through series resistors R13 and R14 and the load circuitry thereof. The stage 38 output is a dc. signal having amplitude indicative of the rate of typing activity. R13 is preferably a variable resistor settable by input to knob 42 for reasons discussed in detail below. Final stage 40 of signal rate detector 20 comprises an emitter-follower including 05, the output signal of which is applied to line 22.

Motor speed modifier 24 of FIG. 2 includes a first grouping of stages incorporating 06-09, operative to provide inputs to Q10 effective to stop record transport or to restart record transport and permit the abovementioned preset speed operation thereof and a second grouping of stages incorporating Q9, Q10 and Q1 1, Q9 and Q11 being operative to provide inputs to Q10 which provide for variation in transport speed between such stopped andpreset speed limits. Q10 is seriesconnected between lines 26 and 28, thereby being in series circuit with the transcriber PLAY switch 44 and voltage supply 46 of energizer l4 and brushes 48 and armature 50 of motor 12.

Considering initially the last-discussed, or nonswitching stage grouping of speed modifier 24, the collector of 011 is connected to the base emitter-follower Q9 whose emitter is connected to the base of Q10. As will be evident, conduction in Q10 decreases with increases in the dc. level on line 22 connected to the base of Q1 1, i.e., with greater negative voltages on line 22. Such greater negative voltage occurs on line 22 with higher rates of typing activity. Conversely, upon a decrease in typing activity rate and hence in the dc. level on line 22, i.e., a lesser negative voltage, conduction in 010 increases. The speed of motor 12 being generally proportional to the voltage at the emitter of Q10, motor speed change is inversely related to the amplitude of line 22 signal by the grouping of stages including Q9, Q10 and Q11.

The other stage grouping of modifier 24 comprises, in effect, a bi-level voltage-sensitive snap-action switch. For motor speed at the above-discussed preset speed, 09 and Q10 are highly conductive, O8 is substantially non-conductive and O7 is also substantially nonconductive since its base potential is governed by junction point P which is maintained by Q9 and the voltage divider comprising R20 and R26 at a potential more negative than the emitter of Q6. Line 22 is at a first potential more positive than that of junction point P. As the line 22 potential goes to a second potential, more negative than the potential at P (which occurrence may be preset to occur at a first preselected rate of typing activity by setting of the wiper of R13 by knob 42), Q7 conducts through R19 and R21, thereby rendering Q8 conductive. With 08 conductive, the potential at the base of 09 becomes less negative and Q9 conduction decreases. As 09 conduction decreases, Q7 conduction increases, since potential at P is free of control by Q9 and becomes less negative, and 010 is rendered substantially non-conductive, thereby changing motor 12 excitation from its prior first level (preset speed), or, more precisely, from the level of excitation then determined by the grouping of stages including O9, 010 and 011, to a second level, substantially zero, and in any case below the excitation level at which motor rotation and record transport occurs.

Such interruption of transcriber operation, brought on by increased rate of typing activity, persists until line 22, by virtue of decreased typing activity rate, reaches a second potential, less negative than the then-existing point P potential, at which time Q7 and hence Q8 are rendered substantially non-conductive and Q9 and hence Q are rendered highly conductive. Motor 12 is thereby reenergized to its first energization level and rotates at its preset speed. It is to be noted particularly that such restarting of record transport need not await the cessation of typing activity but occurs upon the decrease of typing rate to a second preselected rate lower than such first preselected rate. Continuous typing activity is thus enabled. The potential at P reverts to a potential more negative than that of the emitter of Q7 and the snap-action switch remains in such state until typing activity rate again exceeds the rate required before the first-discussed switch actuation can recur.

In the use of the transcriber of the invention, the typist preferably initially sets knob 42 such that the wiper of R13 engages the resistor in the vicinity of its upper extremity. She thereafter operates the transcriber PLAY button and types the recorded text at her customary rate. As her typing rate increases to catch up with the recorded text, Q9, Q10 and Q11 first coact to reduce motor energization smoothly by as much as is tolerable against the criterion of intelligible speech reproduction. In the event that the typist must increase her rate to a still higher level in catching up with the transcriber, a typing rate is ultimately reached at which the first above-discussed switch actuation occurs in modifier 24. At that time, motor 12 is deenergized and remains so until the typing activity rate decreases to a rate at which the second above-discussed switch actuation occurs in modifier 24.

If the typist finds that transcriber record transport is discontinued too frequently based on her initial setting of knob 42, she need only lower the setting thereof. As will be evident from the discussion of the FIG. 2 system, lowering the setting of knob 42 moves the wiper of R13 downwardly and thereby increases the rate of typing activity necessary to effectuate recordtransport discontinuance. Once such initial set-up is achieved the transcriber needs no further adjustment where it is used by this typist.

FIG. 3 shows circuit means for optional use in connection with the FIG. 2 system to further expand the adaptive character thereof. In overall function, the FIG. 3 circuit means provides for peak detecting and storing the line 22 rate indicating signal over a relatively extended time period, e.g., the time taken in the typing of a few lines, to develop a signal indicative of the peak typing activity during a time interval. Such signal is employed to insert a bias at point P for purposes of modifying the P potentials which, as discussed above, establish the typing activity rates at which switching occurs in the first stage grouping of modifier 24. The FIG. 3 circuit means is thus effective, e.g., where a typist may improve in basic typing speed during such interval, to elevate the typing activity rate which must be exceeded prior to modifier 24 switching which discontinues excitation of motor 12 by energizer 14.

The illustrated FIG. 3 circuit means comprises a first stage including emitter-follower Q12 and a charging circuit including R27 and C8, and a second stage including emitter-follower Q13 and output resistor R28.

The base of 012 is connected to line 52 of FIG. 2, the collectors of Q12 and 013 are connected to line 54 of FIG. 2, and R28 is connected to line 56 of FIG 2. Where the transcriber includes the circuit means of FIG. 3, the foregoing initial set-up is unnecessary and R13 may comprise a fixed resistance. On the other hand, the FIG. 3 circuit means may be employed in conjunction with a variable R13 as discussed above.

FIG. 4 illustrates further circuit means for optional use in connection with the FIG. 2 system. In overall function, the FIG. 4 circuit means provides a signal to motor 12 of polarity opposite to the excitation provided thereto on line 28.'Such signal, comprising a pulse, occurs concurrently with the first-discussed switch actuation in modifier 24 and is effective to provide positive braking of the motor.

The-FIG. 4 circuit means comprises three stages including Q14, Q15 and Q16 connected to a voltage supply 58, so as to provide, in response to a voltage level receding negatively on line 60, a pulse increasing positively onoutput line 62.

TABLE I R1 68 K 01 2N4l4 R2 22 K ()2 2N4l4 R3 4.7K Q3 2N4l4 R4 2.2K Q4 2N4l4 R5 I00 K 05 2Nl305 R6 6.8K Q6 2Nl305 R7 33 K Q7 GES R8 6.8K Q8 (IEZZ R9 68 K Q9 2N4l4 R10 2.2K O10 2Nl539 R11 IOOK Q11 2N4l4 R12 2.2K Q12 2N4l4 R13 10 K 013 2N4l4 R14 6.8K Q14 2N414 R15 2.7K Q15 2N4l4 R16 6.8K Q16 2NI539 R17 2.7K

R18 1 K C1 0.1g. R19 470 '0. C2 l ;1. R20 4.7K C3 0.1g. R21 l0 K C4 0.l;.t R22 10 K C5 1 u R23 4.7K C6 I00 11. R24 22 0 C7 1000 p. R25 I0 0 C8 300 p. R26 680 0 C9 10 p. R26A 4.7K

R28 470 (I D] [N456 R29 22 K D2 IN456 R30 22 K D3 IN456 R31 6.8K D4 HEPI56 Sources 46, 58 6 volts As will be noted, transcribers in accordance with the invention can derive all of their automating control'information without reference to the information content of the record being transcribed. It should nevertheless be evident that such transcribers may readily incorporate means deriving additive or secondary control information from the record or other sources.

Various changes and modifications of the invention will be evident to those skilled in the art. For example, in the FIG. 2 preferred embodiment of the signal rate detector of FIG. 1, stage 36-and the preceding circuitry of FIG. 2 may be omitted where the keystrokeresponsive signal generator provides like output pulses for each operated key. Similarly, transcribers'of the invention need not themselves include such signal generator where the typewriters with which the transcribers are used provides such like output pulses. Typing activity within the scope of the invention evidently includes the operation of keys adapted to make an informational imprint, and may include the operation of keys performing non-informational imprint functions. The foregoing preferred embodiments of the transcriber control system are thus intended in a descriptive and not in a limiting sense. The true spirit and scope of the invention will be evident from the following claims.

What is claimed is:

l. A record playback machine for use in the typing of pre-recorded information, comprising:

a. record drive means transporting said record at preset speed on energization thereof;

b. first means generating an electrical output signal on each occurrence of a typing key-stroke;

c. second means generating output signals indicative of the rate of occurrence of signals generated by said first means; and

d. third means receiving said second means output signals and operative to energize said record drive means where said second means output signal occurrence rate is less than a first preselected rate and further operative to dcenergize said record drive means where said second means output signal occurrence rate indication exceeds a second preselected rate.

2. The transcriber claimed in claim 1 further including fourth means operatively responsive to said third means to provide braking of said drive means where said second means output signal occurrence rate indication exceeds said second preselected rate.

3. The transcriber claimed in claim 2 wherein said second means comprises a microphone.

4. The transcriber claimed in claim 1 further including fourth means generating an output signal indicative of the peak occurrence rate indication of said second means output signals during a time interval, said third means increasing said first preselected rate in accordance with increases in said fourth means output signal.

5. The transcriber claimed in claim 4 wherein said second means includes an averaging circuit and provides a direct current voltage indicative of said rate of occurrence of said signals generated by said first means.

6. The transcriber claimed in claim 5 wherein said third means includes direct current voltage-sensitive switch means settable to first state where said direct current voltage provided by said second means is indicative of said occurrence rate indication less than said first preselected rate and settable to a second state where said direct current voltage provided by said second means is indicative of said occurrence rate indication exceeding said second preselected rate.

7. The transcriber claimed in claim 6 further including a voltage source for energizing said record drive means, said switch means providing direct interconnection between said voltage source and said record drive means.

8. A record playback machine for use in the typing of pre-recorded information on a typewriter providing an output signal on the operation of each key thereof, comprising:

a. record drive means;

b. first means for energizing said record drive means at a first energization level;

c. second means generating output signals indicative of the rate of occurrence of said typewriter output signals; and

d. third means receiving said second means output signals and operative to decrease said record drive means energization below said first level to a second level where said second means output signal occurrence rate indication exceeds a first preselected rate and further operative to increase said record drive means excitation above said second level where said second means output signal occurrence rate indication is less than a second preselected rate.

9. The transcriber claimed in claim 8 further including fourth means generating an output signal indicative of the peak occurrence rate indication of said second means output signals during a time interval, said third means increasing said first preselected rate in accordance with increases in said fourth means output signal.

10. The transcriber claimed in claim 8 wherein said second means includes an averaging circuit and provides a direct current voltage indicative of said rate of occurrence of said typewriter output signals.

11. The transcriber claimed in claim 10 wherein said third means includes direct current voltage-sensitive switch means settable to first state where said direct current voltage provided by said second means is indicative of said occurrence rate indication exceeding said first preselected rate and settable to a second state where said direct current voltage provided by said second means is indicative of said occurrence rate indication less than said second preselected rate.

12. The transcriber claimed in claim 1 1 wherein said switch means provides interconnection between said first means and said record drive means.

13. A record playback machine for use in the typing of pre-recorded information comprising:

a. record drive means;

b. first means for energizing said record drive means at a first energization level;

c. second means generating an electrical output signal on each occurrence of a typing keystroke;

third means generating output signals indicative of the rate of occurrence of signals generated by said second means; and

e. fourth means receiving said third means output signals and operative to decrease said record drive means energization below said first level to a second level where said third means output signal occurrence rate indication exceeds a first preselected rate and further operative to increase said record drive means excitation above said second level where said third means output signal occurrence rate indication is less than a second preselected rate.

14. The transcriber claimed in claim 13 further including fifth means generating an output signal indicative of the peak occurrence rate indication of said third means output signals during a time interval, said fourth means increasing said first preselected rate in accordance with increases in said fifth means output signal.

15. The transcriber claimed in claim 13 wherein said second means comprises a microphone.

16. The transcriber claimed in claim 13 wherein said third means includes an averaging circuit and provides a direct current voltage indicative of said rate of occurrence of said signals generated by said second means.

17. The transcriber claimed in claim 16 wherein said fourth means includes direct current voltage-sensitive switch means settable to first state where said direct current voltage provided by said third means is indicaless than said second preselected rate. tive of said occurrence rate indication exceeding said 18. The transcriber claimed in claim 17 wherein said first preselected rate and settable to a second state switch means provides interconnection between said where said direct current voltage provided by said third first means and said record drive means. means is indicative of said occurrence rate indication 5 

